Scientific Method Karen J. Dalton Community College of Baltimore County Catonsville Campus
Observations • What you know before you begin an experiment • Accepted scientific knowledge • Journals, textbooks • What you see in the world around you • What did Semmelweis observe? • What is the problem? Ask a question? • What did he ask? • Hypothesis: Educated answer to your question • Must be based on accepted science • What is your answer to Semmelweis’ problem?
Test you hypothesis • Experimental design • Control groups vs. experimental groups • Large numbers in the groups • Repeatable experiments • How did Semmelweis test his hypothesis? • Results • Data collected as a result of the experiment • Conclusions • What do your results mean? • Results are new observations • Should you now alter your hypothesis?
Theory • Well substantiated explanation of something in the natural world • Explanation uses many different pieces of evidence • Examples: cell, atomic, evolution, chromosomal inheritance • In science this is “as good as it gets” • Lay people use the word theory when they should be using the word hypothesis